Field of Invention
The invention relates to a substrate unit, a display device, and a method for manufacturing the display device.
Related Art
With the advance of technology, flat display devices have been broadly applied to various fields, for example liquid crystal display devices or organic light emitting diode (OLED) display devices. Because flat display devices have superior characteristics of compact volume, low power consumption and low radiation, they gradually replace conventional cathode ray tube display devices and are applied to various electronic products such as mobile phones, portable media devices, laptops, tablet computers, and other display devices.
Because of large-scale, thin and lightweight requirements of a display device, a thinner glass substrate of a display panel is developed from the thickness of 0.5 mm-0.7 mm to the thickness of 0.3 mm (or less). However, if the thickness of the glass substrate is equal to or less than 0.3 mm, the process of forming semiconductor devices for displaying on the surface of the glass substrate cannot be implemented by the existing manufacturing equipment due to thinness and insufficient rigidity of the thin glass substrate.
One conventional solution is to attach a thin glass to another thicker glass carrier plate to increase its rigidity, and then they will be separated after the manufacturing process is accomplished. However, in a subsequent high temperature process (higher than 250° C. for example), silicon and oxygen bonds (—Si—O—Si—) between the glass carrier plate and the thin glass are formed, which results in difficult separation between the thin glass and the glass carrier plate.
Another conventional solution is to attach a thin glass to a glass carrier plate by adhesion using glue material. However, because general glue materials have poor heat resistances, excess glue or bubbles occur during coating. Moreover, some residual glue during separation results in less efficiency for recycling the glass carrier plate.